10521555994 has 4 divisors (see below), whose sum is σ = 15782333994. Its totient is φ = 5260777996.

The previous prime is 10521555977. The next prime is 10521556027. The reversal of 10521555994 is 49955512501.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 49955512501 = 2749 ⋅18172249.

It can be written as a sum of positive squares in only one way, i.e., 10519168969 + 2387025 = 102563^2 + 1545^2 .

It is a super-2 number, since 2×10521555994² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2630388997 + ... + 2630389000.

Almost surely, 2^10521555994 is an apocalyptic number.

10521555994 is a deficient number, since it is larger than the sum of its proper divisors (5260778000).

10521555994 is an equidigital number, since it uses as much as digits as its factorization.

10521555994 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5260777999.

The product of its (nonzero) digits is 405000, while the sum is 46.

The spelling of 10521555994 in words is "ten billion, five hundred twenty-one million, five hundred fifty-five thousand, nine hundred ninety-four".